1. Field of the Invention
The present invention relates generally to radio equipment, and more particularly, to radio equipment for compensating electrical power or characteristics of transmission signals through feedback of the transmission signals.
2. Description of the Related Art
Such radio equipment, for example, is disclosed in the Japanese unexamined patent publication No. 1996-223075, in which some transmission signals transmitted from an antenna are fed back to a generation circuit of the transmission signals, and thereby levels or characteristics of the transmission signals are detected. The levels or characteristics of the transmission signals transmitted from the antenna are compensated based on the detected levels or characteristics of the transmission signals.
More specifically, the radio equipment transmits the transmission signals transmitted from the antenna to the generation circuit of the transmission signals using a reception circuit to feed back the transmission signals, so that the transmission circuit and the reception circuit can be implemented as a very small-scaled circuit construction.
However, it is disclosed that the foregoing radio equipment simply uses a reception unit to feed back the transmission signals, but that transmission and reception signals allowing for the most effective use of the radio equipment are ones based on the TDD (Time Division Duplex) mode in which transmission operation does not concur with reception operation. Further, it is only described in the document that the radio equipment may be applied to signals based on the FDD (Frequency Division Duplex) mode in which transmission operation concurs with reception operation, but that it is necessary to momentarily stop the reception signals (i.e., to remove a sound) by means of a certain method in order to measure characteristics of the transmission signals. However, there is no disclosure with respect to a concrete method.
Consequently, even though the radio equipment may be applied to the transmission and reception signals based on the FDD mode, the conventional radio equipment has a problem in that it cannot compensate the levels and characteristics of the transmission signals transmitted from the antenna utilizing a small-scaled circuit construction.